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Q. M. Zhang, H. Li, M. Poh, F. Xia, Z. Y. Cheng, H. Xu and C. Huang, “An All-Organic Composite Actuator Material with a High Dielectric Constant,” Nature, Vol. 19, No. 419, 2002, pp. 284-287. doi:10.1038/nature01021

has been cited by the following article:

• TITLE: Solvent-Induced Phase-Inversion and Electrical Actuation of Dielectric Copolymer Films

  AUTHORS: Yeonju Jang, Toshihiro Hirai

  KEYWORDS: Actuator, Acrylic Triblock Copolymers, Electrical Actuation, Dielectric Properties

  JOURNAL NAME: Materials Sciences and Applications, Vol.2 No.3, March 7, 2011

  ABSTRACT: Block copolymers posses inherently the ability of form a variety of phase-separated microdomain structures. The lengths of block segments and the selectivity of the solvent are primary factors affecting the resultant morphology. This paper investigated the effect of casting solvents on the morphologies and electrical actuation of poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) (PMMA-PnBA-PMMA) triblock copolymer films comprising PMMA hard segment and PnBA soft segment. Transmission electron microscopy and confocal laser scanning microscopy observation revealed that PMMA and PnBA segments were assembled into various micro- and nano-sized phase structures where either of them formed continuous phase. This implies that continous phase could be inversed by used casting solvents. Solvent-dependent phase morphologies had a significant effect on the electrical actuation results. Increase of the PnBA contents and the continuous phases of PnBA soft segments improved both of electrical actuation and dielectric constant, indicating that solvent-induced phase separation modulates the electrical actuation of dielectric films. The significance of the role of solvent selectivity and the major continuous phase of the polymer in defining the morphology and electrical actuation of the self-assembled block copolymer structure are discussed.